Bloomery

I believe you are referring to an iron melting cupola. The name Steve Chastain along with cupola on a Google search should yield more information and a book on how to construct one.

The product of a cupola furnace would be cast iron, not forgeable steel. Maybe this fellow was whipping up a fresh batch of wootz by the thermite process.

Mike Mandaville

Are you sure that the stuff flowing out the opening was iron? If it was indeed a "bloomery", they would tap off the slag from time to time. If he simply got the stuff out of the furnace and forged it, then that would have to be the case. But, in that case, he would have to eventually let the furnace cool, open it up and take out the solid "bloom" to consolidate (by heating and hammering) the bits of iron or steel that has formed. This "bloom" often looks like a big black clinker with tiny bits of charcoal stuck in it.

When you saw the material flowing out of the furnace, was it being captured in a crucible or directed into a trough for casting into roughly shaped items? If so, then is WAS cast iron, not wrought iron. If, however, the material running out of the furnace was simply being allowed to run out and cool in a puddle, then it probably was a wrought iron production setup.

Here's my favorite place for small scale wrought iron manhfacture. Also, google "rockbridge bloomery" for more places to get info about this group and what they have been doing. We saw them several years ago at the Flagstaff AZ ABANA conference and I'd say they have a better understanding of how to ACTUALLY do it than anybody I have ever met.

-------------------

Iron or steel ? A bloomery works with a bloom, not a melt. This is pretty fundamental. The composition varies between iron through to blister steels.

Melting is usually done with iron, in a cupola furnace. This won't work for steel.

If you're melting actual steel, then you're into the territory of either Huntsman's crucible cast steel and its sophisticated ceramics workign to make the enclosed crucibles. Modern furnaces with modern refractories could use either arc, muffle or reverbatory furnaces without ruinign steel metallurgy.

Thanks to all for the feed-back.

The problem is that when I was there, the man only explained (in Korean) what he did, indicating his equipment. I did not see him actually working live (though he did simulate his hammering).

I only saw a video (from a national documentary show) of him in action, and there was so much to see that went by so fast, so I can't be positive that what I saw was actually molten though that's what my notes indicate. The man uses the product (which he called in English "pig iron") to repeatedly hammer and heat into steel which he finally makes into steel sword blades, which are replicas of historic Korean swords based on his museological, metallurgical and practical research.

'Any more comments?

I havent a clue about Korean techniques, but this is a typical process for any sword-making tradition from the medieval period to the 18th century.

You begun with a billet of crude pig iron. Surface carburisation turns this to a blister steel and repeated cut-weld-draw down cycles make this into a high quality steel. The final result varies from surface hard through laminated pseudo-damascus to pattern-welded steels.

There's a good description in Leon Kapp's excellent Japanese sword book.